Finding the Third Proportional to 1,966.78 and 3,139.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,966.78 : 3,139.59 = 3,139.59 : x
2. Step 2: Convert to fraction form
   1,966.78/3,139.59 = 3,139.59/x
3. Step 3: Cross multiply
   1,966.78x = 3,139.59 × 3,139.59
4. Step 4: Simplify right side
   1,966.78x = 9,857,048.92
5. Step 5: Solve for x
   x = 9,857,048.92/1,966.78
6. Step 6: Final answer
   x = 5,011.77